Feature has been has been removed and its controlling variable innodb_lazy_drop_table has been deprecated from Percona Server 5.5.30-30.2. Feature has been removed because the upstream DROPTABLE implementation has been improved when bugs #56332 and #51325 were fixed.

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(1, 2, 3) Feature has been deprecated after Percona Server 5.1.66-14.2 and Percona Server 5.5.28-29.2. It has been replaced by the upstream innodb_checksum_algorithm implementation released in MySQL 5.6.3.